Significant figures is one of the most commonly confused concepts in science and many students lose marks as a result of using an inappropriate number of significant figures. Hopefully, this little course will help you understand what significant figures are, where they come from, why they are important and how to deal with them when reporting the results of calculations and experimental measurements.
When reporting a measurement, it is important to write the correct number of digits so the measurement is not more accurate than the equipment. For example, if you pour a glass of water into a cylinder and you get a reading of 125.5 ml, clearly it wouldn't be honest if you wrote 125.5734663 ml as your measurement. However, if you divide 125.5 ml into 3 parts, your calculator will give you a very long answer - 41.8333333333 ml. In practice, you would not be able to accurately measure that number of decimal places since your instrument is not fine enough, so you would have to round that number sensibly.
There are many rules surrounding rounding of significant figures. Our 6 Days Six Fig Challenge Course will help you master significant figures and how to apply in your chemistry calculations.Join the course